Plastic bonded smoke

ABSTRACT

An improved method of manufacture of a smoke mix and a smoke mix composition for use in munitions; the improvement being a structure having a smoke producing material and an oxidizing material, such as potassium chlorate, bonded together by a polymer system. The bonding is accomplished by mixing the oxidizing material, smoke producing material, and polymer system to a homogeneous mixture which is a castable or extruable mass; casting or extruding the mass into a desired geometric configuration for use in muntions; and allowing the mass to cure.

llited States Ptet [1 1 Gerber et a1.

[ 1 Apr. 10, 1973 1 1 PLASTIC BONDED SMOKE [75] Inventors: Melvin N. Gerber, Randallstown; Woodrow W. Reaves, Baltimore, both of Md.

[73] Assignee: The United States of America as represented by the Secretary of the Army [22] Filed: Nov. 27, 1970 [21] Appl. No.: 93,207

[52] US. Cl ..l02/65, 149/85 [51 Int. Cl ..F42b 27/06 [58] Field of Search 102/6, 64, 65, 90;

[56] References Cited UNITED STATES PATENTS 1,894,203 1/1933 Spring ..102/65 3,121,394 2/1964 Anzalone ..149/85 X 3,309,249 3/1967 Allen 149/44 X 3,338,763 8/1967 Kristal 149/85 X 3,509,243 4/1970 Moore... .....149/83 3,650,856 3/1972 Artz 149/44 Primary Examiner-Verlin R. Pendegrass Att0rneyl-1arry M. Saragovitz, Edward J. Kelly, Herbert Berl and Bernard J. Ohlendorf 5 7 ABSTRACT 4 Claims, 2 Drawing Figures lllill)) PATENTEU 3,726,225

l F1 12 ml- 1 1 v 1 7 3 51W 5 x i a i i W w a; "IL-hum INVENTORS Melvin N. Gerber Woodrow .W. Real/es PLASTIC BONDED SMOKE DEDICATORY CLAUSE The invention described herein may be manufactured, used, and licensed by or for the Government for governmental purposes without the payment to us of any royalty thereon.

Our invention relates to a method of mixing and loading smoke mixes in munitions and a composition for use as smoke mixtures in conventional munitions.

Prior art smoke mixtures, such as disclosed in U.S. Pat. Nos. 3,229,633 and 2,419,851 were known as dry mixtures and created many safety and handling problems during mixing operations and in loading the mixes in munitions. For example, prior art smoke mixes introduced a hazard of fire and premature detonation due to inherent sensitivity of the mixtures and their dusts, introduced hazards due to the utilization of volatile flammable solvents when granulating processes were employed, and necessitated the use of high pressure pressing techniques during munition loading operations. Our invention was conceived and reduced to practice to solve the above described problems and to satisfy the long felt need for a smoke mix and a method of mixing and loading the mix in munitions which is not sensitive and conducive to fire and premature detonation hazard, does not necessitate the use of volatile flammable solvents, and does not require the use of high pressure pressing techniques during loading operations of the mix of our invention into munitions.

A principal object of our invention is to provide a smoke mix and method for mixing and loading the mix into munitions which is not conducive to the hazards of fire and premature detonation.

Another object of our invention is to provide a smoke mix and method of mixing and loading the mix into munitions which does not necessitate the use of volatile flammable solvents.

A further object of our invention is to provide a smoke mix mass which can be either extruded or cast to any geometric shape under relatively low pressure without the use of a mold and which can be loaded into munitions without requiring the use of high pressure pressing techniques during the loading operations of the smoke mix mass into munitions.

A still further object of our invention is to provide a smoke mix and manufacturing technique which increases the efficiency and safety of the loading operation of the smoke mix into munitions through the utilization of extrusion and casting equipment in manufacturing the smoke mix.

Other objects will be obvious from or will appear in the specification hereinafter set forth.

FIG. 1 is a top view ofthe munition shown in FIG. 2.

FIG. 2 is a view ofa munition using our smoke mix.

Our invention and FIGS. 1 and 2 will now be described in detail as follows.

The grenade shown at l in FIG. 2 is loaded with the smoke mix 2 of our invention and cup plate 3 is superimposed on the smoke mix. Cup plate 3 contains a hole in the bottom thereof to permit ignition of the payload by the first fire means 4 inserted within the cup plate. First fire means 4 can be any conventional means such as utilized with the device disclosed in U.S. Pat. Nos. 3,434,421 and Re. 18,938 or the first fire means disclosed in pending U.S. patent application Ser. No.

86,450 filed Nov. 3 1970 and described in Example 1 below. 1

EXAMPLE 1 Component Parts Viscosity Density at 25C by weight at 25C Thioepoxy Resin 20 i 10 116 Poises 1.26 gm/cc Mercaptan 20 :10 1.3 Poises 1.14 gm/cc Plasticizer 17 i 17 to 240 Sec. Saybolt Universal 12.04 lbs/gal Acrawax C 0 to 10 Potassium Chlorate 40 i 20 Sodium Bicarbonate 0 to 9 Each component listed in the above example is placed in a conventional blender and mixed until a homogenous slurry is obtained. Sodium bicarbonate is utilized to decrease the amount of flame generated on ignition of the first fire means and to shorten the amount of time to cure the slurry. Acrawax C is utilized to reduce the first fire means impact sensitivity;.the greater the amount of Acrawax C content, the lesser the impact sensitivity. After a homogenous slurry is obtained, the slurry is poured into molds having a suitable configuration to suit a given application and permitted to cure in the conventional manner. The time and temperature for curing of the slurry depend on the particular resin, mercaptan, and plasticizer employed; particular components in the above example and amounts thereof being selectable and adjustable within the skill of the art to produce a flexible, rubbery, and waterproof first fire means. After the slurry has cured, the plastic bonded first fire means is assembled within munitions. First fire means 4 is ignited by a conventional delay column 5 which is integral with conventional firing mechanism 6', firing mechanism 6 being fixedly mounted within cover means 7 in the conventional manner, such as threadably as shown in FIG. 2. Our improvement, smoke mix 2, is a plastic bonded and unit constructed subcombination which is placed within case 8 and requires no high pressure pressing technique or use of flammable solvents to manufacture and insert mix 2 within munition 1. An exemplary composition for our smoke mix 2 is set forth in Example 2 below.

Each component listed in the above example is placed in a conventional blender and mixed until a homogenous mass is obtained. Sodium bicarbonate is utilized to decrease the amount of flame generated on ignition of the smoke mix and to control the smoke mix burning rate. After a homogenous mass is obtained, the

mass is cast or extruded into configurations to suit a given application and permitted to cure in the conventional manner. The time and temperature for the curing of the mass depend on the particular polymer system employed, and the particular components in the above example and amounts thereof are selectable and adjustable within the skill of the art for our smoke mix. After the configuration has cured, the plastic bonded smoke mix is assembled within munitions as above described. While a grenade is shown in the drawing, our invention can be utilized with any other munition application. Any conventional smoke producing material and dye can be incorporated into our smoke mix. Our smoke mix can also incorporate a unique feature of using dyes containing five parts by weight of nitrocellulose; the dyes being prepared to meet a predetermined particle size distribution suitable to facilitate extruding or casting of our smoke mix for a given application within the skill of the art.

It is obvious that other modifications can be made of our invention, and we desire to be limited only by the scope of the appended claims.

We claim:

1. In a munition having a plurality of components comprising a firing mechanism, a delay column, a container means, and a first fire means; the improvement in combination with the components being a smoke mix within the container means comprising a smoke producing material, an oxidizing material, and a polymer system wherein:

the smoke producing material is a granulated dye in the amount of 20 to 50 parts by weight;

the oxidizing material is potassium chlorate in the amount of 15 to 35 parts by weight; and

the polymer system consists of thioepoxy resin in the amount of 2 to 8 parts by weight, a viscosity of 1 l6 poses at 25C, and a density of 1.26 gms/cc at 25C and a polyamide resin is in the amount of 4 to 24 parts by weight, a viscosity of poises at 25C, and a density of 0.97 gms/cc at 25C.

2. The munition of claim 1 wherein the dye has a predetermined particle size distribution adapted to facilitate extruding the composition and contains 5 parts by weight of nitrocellulose.

3. The munition of claim 2 wherein sodium bicarbonate is a component in an amount no greater than 30 parts by weight.

4. The munition of claim 3 wherein ethylene bis(isothiosemicarbazide) is a component in an amount no greater than 10 parts by weight. 

2. The munition of claim 1 wherein the dye has a predetermined particle size distribution adapted to facilitate extruding the composition and contains 5 parts by weight of nitrocellulose.
 3. The munition of claim 2 wherein sodium bicarbonate is a component in an amount no greater than 30 parts by weight.
 4. The munition of claim 3 wherein ethylene bis(isothiosemicarbazide) is a component in an amount no greater than 10 parts by weight. 